A U.S. Navy P-8 Poseidon surveillance plane had an “unsafe interaction” with a Russian SU-30 fighter jet this Saturday that used its afterburners as it flew in front of the American plane over the Black Sea, according to a U.S. official. It was the first unsafe encounter for a U.S. military aircraft in months.

According to the U.S. official, the Navy plane was flying over the Black Sea when it was intercepted by a Russian SU-30 “Flanker” fighter.

At its closest point, the Russian fighter came as close as 50 feet to the Navy aircraft, but it was a maneuver flying in front of the American plane that has led to the U.S. labeling the encounter as unsafe.

Moving from right to left, the Russian fighter then activated its afterburners as it flew in front of the American plane.

The official said the Russian fighter’s move caused a turbulence wake in front of the American plane that led it to roll as it flew through it.

The Pentagon has deemed the Russian aircraft’s maneuver as an “unsafe interaction”.

This weekend’s unsafe interaction is the first unsafe encounter in months involving a Russian aircraft.

The U.S. military uses various criteria aside from distance to determine whether an encounter with a foreign military vessel or aircraft should be classified as unsafe.

For example, the speed of an aircraft and rate of closure can factor more than a close distance in an air encounter.

Such was the case in May over the Black Sea when a Russian fighter’s coming within 20 feet of a P-8 aircraft was deemed “safe and professional.”

At the time, a U.S. official said that was the case because both aircraft visually identified each other and the Russian aircraft approached the American plane in a professional manner.